Threat Descriptons



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Type :


Aliases :

Dod.A, Email-Worm.Win32.Dod.a


Dod.A is an email worm that spreads using several different languages. It also drops a variant of Rbot on the infected system.


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Technical Details

Installation to system

When run, the worm drops the following three files from its resource:


'bx.exe' is a copy of Rbot. 'bszip.dll' and 'ANSMTP.DLL' are used later in email spreading. The work also writes the following files in the Windows system folder:

The contents of these files are characters 'MZ'. As 'com' extension is evaluated before 'exe' in Windows program execution, this trick tries to disable the execution of above programs with 'exe' extension.

The worm executes 'bx.exe' which installs itself in system. This file is a variant of Rbot. When 'bx.exe' is run, it copies itself as 'winis.exe' in the Windows system directory and adds the following registry keys:

"IE Runtimes" = "%SysDir%\winis.exe"

This ensures that it will be executed at next system startup. The bot can be used as a backdoor, collecting system information, logging keystrokes, relaying spam and for various other purposes.

The worm also opens a jpg-file from predefined URL. The picture looks like this:

email spreading

Dod.A gathers email addresses from the MSN messenger contact list. The worm uses the dropped SMTP component (ANSMTP.DLL) to send infected messages. It can construct the messages in 7 different languages. The language is selected using the locale of the infected computer.

Here are the possible english messages:

Attachment Returned
This file was rejected by the recipient
You suck!
I have enclosed why you suck and your not going to like it :@
My new details
Hi i've changed email address if you would like to 

keep in contact i have enclosed my new details
Party Invite!!
You have been invited to my party 

please download the details and tell me if you 

will be able to make it , Thanks!

Here are the possible german messages:

Zubeh r Ging
Diese Akte wurde von der Empf nger zur ckgewiesen
Sie saugen!
Ich habe umgeben, warum Sie saugen und Ihr Gehen nicht zu wie ihm :@
Meine neuen Details
Hallo nderte ive email address, wenn Sie zu m chten 

Unterhalt im Kontakt habe ich meine neuen Details umgeben
Beteiligtes Laden!!
Sie sind zu meinem Beteiligten eingeladen worden 

ddownloaden Sie bitte die Details und erkl ren Sie mir 

wenn Sie in der LageSIND, es zu bilden, Dank!

Here are the possible french messages:

L'Attachement Est retourn
Ce dossier a rejet par le destinataire
Vous sucez!
J'ai enferm pourquoi vous sucez et votre ne pas aller comme lui :@
Mes nouveaux d tails
Bonjour l'ive a chang le email address si vous voudriez 

subsistance en contact j'ai joint mes nouveaux d tails
La Partie Invitent!!
Vous avez invit ma partie t chargez 

svp les d tails et me dites si vous pourrez lafaire, merci!

Possible italian messages:

Il Collegamento Ha rinviato
Questa lima stata rifiutata dal destinatario
Ho accluso perch succhiate e vostro non andare come ad esso :@
I miei nuovi particolari
Hi il ive ha cambiato il email address se gradiste a 

conservazione in contatto ho accluso i miei nuovi particolari
Il Partito Invita!!
Siete stati invitati al mio partito prego 

trasferite i particolari dal sistema centrale 

verso i satelliti e mi dite se potrete farlo, ringraziamenti!

Possible portuguese messages:

O Acess rio Retornou
Esta lima foi rejeitada pelo receptor
Voc suga!
Eu inclu porque voc suga e seu n o lhe ir como :@
Usted aspira!
He incluido porqu usted aspira y el su no ir como a l :@
O Partido Convida!!
Voc foi convidado a meu partido download por 

favor os detalhes e diz-me se voc pudesse

fazer, agradecimentos!

Possible spanish messages:

El Accesorio Volvi
Este archivo fue rechazado por el recipiente
Usted aspira!
He incluido porqu usted aspira y el su no ir como a l :@
Mis nuevos detalles
Hi el ive cambi email address si usted quisiera a 

mantener contacto he incluido mis nuevos detalles
El Partido Invita!!
Le han invitado a mi partido descarga por favor 

los detalles y me dice si usted puede hacerlo, 


Possible dutch messages:

Het aanhechtsel Keerde Terug
Dit bestand werd door de ontvanger afgekeurd
U zuigt!
Ik heb waarom u zuigt bijgevoegd en uw gaand alsof het niet :@
Mijn nieuwe details
Hi veranderde ive email aanspreekt of u van naar zou houden 

Hou in contact ik heb bijgevoegd mijn nieuwe details bij
De partij Uitnodig!!
U bent naar mijn partij alstublieft download de detailsuitgenodigd worden en vertel mij indien u hem zult kunnenmaken, Bedankt!

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